Manufacture of artificial threads



Dec'. 1,1931. 4 P. sc HLAcK 1,834,806v

` MANUFACTURE OF ARTIFICYIAL THREADS Filed March l, 1928 2 Sheets-Sheet l Dec. 1, 1931. P SCHLACK 1,834,806

MANUFACTURE 0F ARTIFICIAL THREADS Filed March l. 1928 2 Sheets-Sheet 2 Af/M ff; new ar per @ha my M Patented Dec. 1, 1931 UNITED Asfifa'res PATENT GFFICF.;

PAUL ISCHLACK, F BEBLIN-KARLSHOZRST, GERMANY, ASSIGNOR T0 ACETA G. M. B. P., 0F BERLIN-LIGHTENBERG, GERMANY, A CORPORATION OF G-EQJIH/[ANY MANUFAGTURE 0F AARTIFICIAL THREADS Application tiled March 1, 1928.Sera1 No. 258,430, and in. Germany March 3, 1927.

vThe present invention relates to improvements in the manufacture otl articial silk threads by the dry spinning process.

In the manufacture of artificial silk 'by the dry spinning'process the voperation is generally such that the several threads after leaving the nozzles Iare drawn downwards against a current of Awarm air which enters into the spinning cells yat the bottom thereof and lleaves at the upper part laden with vapor of solvent.

The use of the counter-current in drying the threads favors a gradual controlled solidilication of the threads, a condition which is of the greatest importance for the properties of the thread. Practically, the suction of the air upwards has the great disadvantage that irregular currents of air are apt to occur in the spinning chamber whereby the progress of the spinning is unfavorably affected. I

These air currents are so much more in- `iurious as they appear more strongly just in the most sensitive place of the formed fibers, namely at the suction-opening in the neighborhood of the nozzle so that they easily cause disturbances at the nozzle, the adhesion of separate threads to each other and the forma-tion of faults in the product.

These disadvantages are the more apparent when the partitions forming the several chambers'are perforated with the object of equalizing injurious diferences of temperature and content of vapor of solvent within the several cells of the group constituting the chamber.

According to the present invention, the spinning can be considerably improved by subdivi'ding each of the spinning cells by a constriction at a suitable level in the cell, so that there are formed two cells, both of which are connected at the upperk end in controllable manner and independently of each other with the suction pipe, the movement of air being sovadjusted that a more or less-large part of the warmed air introduced from below and containing Vmore or less vapor of solvent, if the known circulation is used, is withdrawn from the lower cell so that a comparatively small volume of air laden with vapor of solvent is led through the higher subdivision. The subdivision of the spinning cells may be effected advantageously by movable flaps arranged to form a sort of funnel, so that it is possible to widen the passage for the thread during spinning without damaging the thread.

The invention insures that there is only an extremely slight and very uniform movement of air in the upper part of the spinning cell and that the several spinning cells may be put into communication with each other for the purpose of equalizing diiferences of temperature and content of vapor of solvent without objection. It is unimportant whether both parts of the subdivided cell are thus/put into communication with adjacent cells or onlythe upper part; it is in the latter that the physical conditions are of first importance for the properties of the finished fiber.

A special advantage of this mode of operating is that even on opening the upper and lower doors of thespinning chamber neither the spinning operation in the cells in question nor the use of the perforated chamber walls of the neighboring cells is markedly affected, especially when the lower cells are separated from each other by walls which are not perforated; this advantage does not exist in the known arrangement.

Finally, the subdivision of the cells allows for varying the heating in the two parts independently of each other,which is of im portance when silk of ditlerent titer is to be produced by one and the same machine, in which case one must operate under otnerwise similar conditions with different quantities of air.

The annexed diagrammatic drawings represent an apparatus for carrying out our invention. InA these drawings Fig. l is an elevation ot an individual cr Fig. 2 is an elevation in c1 ,ss-section of a number of cells arranged in series so as to form a single operating unit:

lig. 3 is a plan view on an enlarged scale of the arrangement ofilaps employed forsubdividing the cell into two compartments.

In these drawings, a represents the upper compartment divided from the lower compartment Z) by aps d, turning on hinges o; the opening and the closing of the flaps is effected by any suitable known device7 which, however, is omittedfor the sake of clearness. The Vfilament is extruded through nozzle e and after passing throughthe compartments a and' Z) is withdrawn from the cell below the 4lid over a thread guide n; the upper lid f1 is provided so as to render the nozzle .c easily accessible; g and hare independently regulated heating systems for the cell compartments a and bythe air necessary for drying the laments enters at The major portion is withdrawn at 7c in the neighborhood of the funnel-like aperture vformed by the flaps d, whereas the remainder is withdrawn` at Z near thek nozzle c. In Fig. -2 the partitions m between the individual cells effectively prevent circulation of the drying medium in the lower 'part of the cells, i. e. between the individual compartments I). In the upper compartments a the partitions m are perforated overtheir whole length so asjto allow cfa thorough equalization of difference arising in the lphysical "conditions of the atmosphere contained in the individual cells. In Fig. 3, 0 denotes levers .which'actuate the fiaps CZ. Y o

What I claim is:

' l. In a dry spinning facture of artificialv silk threads, -in which the drying is effected by an ascending current of a gaseous medium in counter-current to the silk fila-ments issuing from the Y one part ofsaidV drying mediumat a mediumY 40 .level of its path of lContact with the filaments Vthe nozzle. Y

nozzle, the steps consisting in withdrawing and theother part in proximity to the point of issue of said filaments from the nozzle.

process for the` manu- 4. A cell according to claim 3 in which the constriction is formed by fiaps capable of turning on hinges and arranged so as to constitute a funnel-like adjustable aperture.

5. Apparatus for the manufacture of artificial silk consisting ofa plurality of cells according to claim 3 arranged in series, and means provided' in the walls common to the upper compartments of adjacent cells for communication between said upper comp artments. A i' 6. Apparatus forthe manufacture of articial silk consisting of a plurality of cells according to claim Sarranged in series, and perforations provided in thewalls common to the upper compartments of adjacent cells for communication between said upper compartments.Y l i 7. Apparatus for the manufacture of artificial silk consisting of a plurality of cells according to claim 8 arranged' in series7 means provided in the walls common to the upper compartments of adjacent cells Yfor communication between saidupper compartments and means for heatingthe upper compartments independently ofV the lower compartments of said cells. y f i .Intestimony whereof, I afx my signature.

PAUL scHLAon.

A2. Ina dry spinning process for the manu- Y i facture of. artificial silk threads, in which the drying is effected by an ascending current ofia gaseous` medium incounter-current to.. the rsilk filaments issuing from the nozzle, the steps consisting -in withdrawing the greater part of said drying medium at a medium level of its path of contact with `the filaments and the other partV in proximity to the point of issue vof said filaments from 3. A Vcell for the manufacture of artificial silk threads bythe dry spinning process in which the drying is effected by an ascending *currentofa gaseous medium in counter-current to the silk filaments, comprising a constriction of the drying cell at a medium level of said cell, forming'twocompartments within said cell, means'ffor withdrawing one part of the drying medium at the upper end of the lower compartment'and means for with,- drawing another partof said medium from .the upper compartment in proximityto the point of issue of the filaments from theinozzle. 

